Dry-pipe sprinkler system



Patented Sept. 14, 1926.

PATENT OFFICE.

ALBERT J. Lonrsmena, or PROVIDENCE, RHODE ISLAND, AssIeNoR,v BY MESNE AssIeNME 'rs, T0 GENERAL Fran EXTINGUISI-IER COMPANY, or PROVIDENCE, nnom; IsLAND, A CORPORATION or DELAWARE.

DRY-PIPE SPRINKLER SYSTEM.

Application filed June 22, 1923.

reason and because the acid is corrosive it is especially desirable to employ the dry pipe principle, in which the pipes remain normally filled with air until a sprinkler opens from the heat of a fire, whereupon the reduction of air pressure automatically trips a valve for each liquid, to admit it to its system of piping leading to the sprinklers. In such cases it is highly desirable that both liquids, travelling through their respective systems, should arrive at the open. head at the same instant, as the required ellect is produced only by mixing, and as either alone may be seriously damaging to goods on which it may fall. It has, however, heretofore been found practically impossible to build two systems thus in parallel so that the valves will operate simultaneously". The present invention has for its ob ect to provide means for theqsimultaneous operat on of. the separate valves controlling the liquids of such a system.

This object is accomplished by providing an operative connection between the two such that either may trip the other, or, more strictly, such that the tripping of either occasions the simultaneous tripping of the other. This is attained. by providing a physical connection between operating parts of the two valves. The invention is here illus trated as it may be applied to a well-known type of dry pipe valve in which the liquid retaining clapper is held seated against the hydrostatic pressure of liquid by a system of linkage which is balanced in unstable equilibrium so that it yields upon slight dislodgment, and there is a weight, held suspended by air pressure in the distribution system, ready when released by fall of the air pressure to descend. and knockthe linkage system out of its said equilibrlum, thus allowing the hydrostatic pressure to open the valve. The area of the yielding mem her which is exposed to the air pressure in the distribution system is so designed, with relation to the constant force. applied to it Such systems employ Serial No. 647,175.

by the weight, that the two are balanced when the air pressure has fallen, as it does upon the opening of a sprinkler anywhere in the system, to a certain predetermined value, which may, for example, be one-sixth of the normal hydrostatic pressure ofliquid. With further falling the air pressure be comes too weak to hold the weight which thereupon descends, allowing the liquid valve to open. lVhere too such valves are side by side, each opening into its own distribution system, the fall of air maybe a little slower in one system than in the other, or there may be slightly more friction in the linkage of one system than in the other, or, for other causes, the two, it entirely independent, may not have their valves tripped precisely simultaneously, even though the air release from them begins simultaneously on the opening of a double sprinkler head. It is a feature of the invention to make this action ofthe valves simultaneous, notwithstanding such diilerences; and this is accomplished by providing aconnection be:- tween the parts which move when the valve is tripped. Specifically, the connection herein illustrated comprises a single air chamber connected with one of the systems of pipes, opposed in common bythe weights or other devices by which the valves in the two systems are tripped, so that neither weight canbe released in order 'to trip its valve without the other weight also being released to trip the other valve. illustrated this end is attained-I by arranging the valves in physical proximity with the weights of each valve held in suspensionfby one arm of its trip lever, the other arm. of which is pressing against the single diaphragm or clapper which reflects the pressure conditions within the distribution. system. It follows that upon. sufficient reduction of the air pressure in that system. so

that the effective pressure on the clapper is less than that required to overcome the upward thrust of the trip levers, both of the latter will swing and allow the weights to fall simultaneously, even though the actual air pressure in each system may not be the same. 1

It will be understood that mechanical. connections may be made in other respects between the parts which move when the tripping occurs, with similar results and. within the scope of the invention. The generic invention, and other species thereof are set forth and claimed in three other applications for patent Serial Nos. 647,172; 647, 7 3;

and 647,174, filed coincidently herewith.

is intended that the present patent shall cover, by suitable expression in the appended claims, whatever features of patentabie novelty exist in the general idea of an air pressure chamber which expresses the iiuid conditions in one or both of the distribution systems and which is used in common bythe valve linkages, so that the weakening of its 7 pressure releases them simultaneously."

well known in the art.

'lelism, the one for carrying acid and the other for carrying an alkali liquid to sprinklers where the alkali and the acid are jetted together or otherwise mixed so as to produce a fire extinguishing liquid, gas or foam. It is understood that each sprinkler is fed from both distribution systems, and opens both when it is released automatically in response to rise of temperature, but such details are not illustrated because they are The dry pipe valves 14 and 24 illustrated are also of a type which are well known and therefore do not need to be described in detail. The liquid retaining air clapper 24 of each system is held closed by a system of linkage including a weighted lever 40 so arranged that when set to be tripped, each weight is hooked, as at 42 and 43, on the power ends of trip levers 44, whose work ends tend to open the single air clapper valve 46 which is normally held on its seat by the air pres sure in one of the two distribution systems. Whenever this air pressure falls to a predetermined amount, as after the opening of a sprinkler, the two weights acting jointly on the single air clap-per lift it and the incidental tipping of the trip levers lets the two weight hooks slip oif from them allowing the weights to fall simultaneously. Each weight in falling swings free a strut 53, that has been on dead center and, by

means of a lever 51, a plunger 50 and a toggle 55, has held the liquid valve of its system closed. The freeing of this strut and the withdrawal of the plunger 50 by a suitably arranged arm. 41 on the lever 40, breaks the'toggle, permits the clapper 24 to open and allows the liquid to rush into the distribution system. Since both weights are released together the opening of their re proper through which the toggle plungers 50 project from chambers 49 into 47 are large enough to allow free passage of fluid, 7

and the contents are kept at atmospheric pressure by the usual ball drip valve (not shown) which closes when a rush of fluid through it begins. The chamber thus affords fluid connection such that if either liquid valve were tripped enough to leak, and the other still held, the inflow of liquid would quickly fill the chamber and apply high pressure to the underside of the hesitating air valve 46, thus insuring its immediate opening and the simultaneous full release, of both liquid valves 24".

It is desirable for the perfect simultaneousness of action thatthere be a communieating passage as'indicated at 32, between the risers 13 and 23, or elsewhere between the air portion of the two systems, so as to provide equality of air pressure in the two systems and on the air clapper 46. Upon the opening of the dry pipe valves and the rush of liquid through the risers 13 and 23 a small quantity of liquid from each flows into the connection 32. r The gas formed at the place of meeting prevents further mingling of the liquids there; and the maintenance of this gas separation may be aided by providing a medial chamber 32 in which the gas is entrapped. With such a communicating passage, the connection to the air clapper chamber'can be made from either riser and is here illustrated as a pipe 39 fromv riser 13 leading to the chamber above the air clapper 46.

The invention can also be used with an "ski (Ill

accelerator 34 whose entrance pipe 35 is 4 shown connected with the pipe 39 at a point between the air clapper and a restriction 39 in the pipe 39. This restriction is large enough to transmit a drop in pressure in the distribution systems to the accelerator to cause actuation of the latter, and small enough to hold up flow thereafter through the pipe 39, while the effective pressure in the ch amber above the air clapper is reduced by transfer of its air through the pipe 35, accelerator 34 and the pipe 36' into either of the intermediate chambers 49, from which, by way of the common chamber 47, and passages 48 by the 'plungers 50, the fluid quickly reaches, and balances the pressure on the air clapper 46, so that the weights can fall. Upon the tripping of the weighted levers each passage around the plunger is closed, for each plunger in moving draws with it a plug collar 50 which seals the openings 48 in the wall of its chamber 49 and thereby prevents leakage of either liquid into the connecting chamber and into contact with the other liquid.

I claim as my invention:

1. A dry 'pipe system for plural liquids, comprising a distribution system and dry pipe valve for each liquid, a control system for each said valve, and an air pressure chamber connected with one of the distribution systems and operative upon both valve control systems to hold the valves closed and to release the valves simultaneously.

2. A dry pipe system for. plural liquids, comprising a distribution system and dry pipe valve for each liquid, a control system for each said valve, and a single air pressure clapper, connected with one of the distribution systems, and held by the air pressure therein against yielding to the tendency of the two dry pipe valves to open.

3. In a dry pipe system for plural liquids, comprising a distribution system and dry pipe valve for each liquid, adapted to be held closed by a weighted lever and adapted to be opened upon said weighted lever being tripped, the combination with a trip lever arranged to hold the weight in suspension,

of a single movable means backed by pressure in the distribution system to oppose the trip lever, yieldably to release said valves at the same time.

l. In a .dry pipe system for plural liquids, comprising a distribution system and dry pipe valve for each liquid, adapted to be held closed by linkage systems and the pressure in the distribution system operating through said linkage systems, the combination, with a single chamber having a movable wall and connected with one said distribution system, of an accelerator connected to the distributing system for its own actuation and connected to the said chamber for voiding pressure therefrom whereby the dry pipe valves may open simultaneously.

5. In a dry pipe system for plural liquids, comprising a distribution system and dry pipe valve for each liquid, adapted to be held closed by linkage systems and the pressure in the distribution system operating through said linkage systems, the combination with a single chamber, having a movable wall and connected with one said distribution system, of an accelerator connected to the distributing system for its own actuation and connected to the said chamber for voiding pressure therefrom, whereby the dry pipe valves may open simultaneously; said connection from the chamber to the distributing system being one which restricts inflow from the distribution system.

Signed at Boston, Massachusetts, this 18th day of May, 1923.

ALBERT J l LOEPSINGER. 

